Latewood's 'little guide' to Lighting...No theory, just info!

hey guys - Im going to start growing this weekend - provided that my seeds arrive, and I have yet to decide on a lighting source.

I am going to be growing in a 3' x 4' closet and I want to spend about $100 or less.. I guess my best choice would be HPS/MH.. and I could just buy the MH bulb now and wait till flowering to buy the HPS.

Any suggestions?

Latewood â?? Thanks for this thread. I understand the different types of lights and their various functions, but Iâ??m confused as to the number of lights needed for a larger (20â?? x 20â?? x 8.5â??) grow room.

Assuming that the room will be used exclusively for either veg or flower at any given time and that the lights will be stationary (i.e. no tracks. Obviously they will be adjustable vertically.) How many HID lights in what kind of configuration would be necessary for optimum crop yield? I guess another way of asking this is what is the optimum effective footprint of a 1000W HID light?

BTW â?? if the plants get too big and bushy, I will supplement with fluorescents in between the rows of plants.

Any advice you can offer is greatly appreciated!

I am not LW, but here is my take on your question. You would need 16 1000 watt HID lights to get 40 watts per sq. ft. To run that many lights you are going to be drawing ~75% of a 200 amp regular service.....lol Each 1000 watt light would cover a 5'x5' footprint. You could grow trees with that kind of lighting. Then adding 216 watt T5's in between plants, wow. DO NOT try to use the microwave when lights are on........LMAO

Drawing 192+ kwh's a day might get someones attention. By the time you add fans, pumps, etc you are going to using 25-30 dollars/day in electricity. Not many households use 900 month in electricity.....lol

If you are not an electrician, I'd get to know one if I were contemplating such a setup, cause you are going to need one. Thats a lotta amps to be dealing with. And, you would need relays or something controlling a lighting setup such as that. You would not want all 16 lights firing off at the same time I would not think.

Please show us pictures if you do this. It would be a killer setup. My peppers, 'maters, cukes, and herbs would be loving life in such a setup. I am envious to say the least.

.5 gram/watt would be ~18 pounds per harvest..........damn. And with a setup like that I would bet you can do much better than .5 gram/watt.

I hope you got deep pockets. I'd bet it would cost 12-15K or more to get a setup like that up and running. Hell, you are going to have 7K+ in lights alone because you are going to want digi ballasts fer sure.

Buy your nutes by the drum.
You will need a "staff" to do the trimming.
Never leave your house, and get a few BFD's (bfd= big fuckin dogs)

Not sure why you would want to veg in that entire space. I'd have a seperate veg area and veg clones under flouro's versus H.I.D. lights. Once you harvest you could toss vegg'd clones in flower room and be on your way to another crop. Not to mention you would save a shitload in electricity by using flouro's to veg with.

Best of luck and keep us posted on the progress. I will be following this thread closely. Will be interesting to see what LW suggests now and if I was even close to suggesting the right equipment.

b0nger

1000watts with efficient reflector is supposed to have a footprint of 8'x8' with that in mind. I would say 9-1000w 3x3. start 4 feet off any wall and space at 8". goodluck.

p.s. heed electrical costs mentioned above.

Bonger and LW - thanks for the advice. Sadly, there's a big discrepancy between the size of the footprints you mentioned. I guess I'll start with the 8'x8' footprint and add more lighting as needed.

As far as the electrical is concerned, I started pulling wire about 35 years ago, so this is a piece of cake. Without bragging, let me say that this will have one of the finest electrical set ups you have ever seen - helll, you'll be able to put a jacuzzi down there so you can sit in comfort and watch your plants grow - well, from an electrical standpoint anyway. LOL

ROFL - Yeah, I could imagine turning on all those puppies at once. 16 lights or 9, wouldn't matter much which. I want to try to find a computer program that will interface with a controller - start everything up in a logical sequence without having to dick around with many various controls.

I'm building a house. The GR goes under the house. Totally self-contained except the intake and exhaust go through the roof of the house above. The house is going to have solar panels, which will off-set a lot of the electrical use. In any event, I live in a Medical Marijuana state so...

The cloning and vegging will actually take place in a seperate room, under flourescents. This didn't seem relevant to my original question, but happy to provide the information.

The budget, yeah... I'm selling my house and building a new one. Have you ever done that before? I have. One day you're standing there with quite a few hundred thousand dollars, just feeling really good about life in general, then 6 months later you're taking out a mortgage because the price of everything went up the moment you started construction. Grrrr Anyway, I'm spending some relatively big bucks on this entire project and the budget & funding are there.

From one standpoint this is just another construction project - Nothing I haven't done before except for the GR. Construction wise, it's a piece of cake. Since the structure is underground, there's not a whole lot of room for changes after the concrete is poured. I have to size some vent pipe and, since the air cooling system for the lights is a big part of my ventilation demand will be those fans, I need to get a good idea of cfm expectations, which requires a ballpark estimate of the number of lights I'm going to need.

What's an efficient number of lights to run on a quality in-line fan, most likely 6" duct? (Just to be clear, the light-cooling system takes in fresh air from outside and exhausts hot air outside. It is completely independent of and isolated from the GR environment.)

Once again, thanks for the great answers!

I cannot answer the...How many inline fans I need...but my guess would be thatb you can't run more than 2-3 max on a fan, and I would even try that. Perhaps Zandor or one of the bigger growers can help you there.

As far as the 8x8 footprint. that is the industry standard, and you can find that info at any national hydro webpage,, under hydrofarm.
100w 8x8
600w 6x6
400w 4x4
250w 2x3feet
common, the same...no debate. fact.

Latewood nead some help mate.Im helping out a freind he is growing in a space of 12ft x 19ft 11ft high currently he is using 4 x 1000 watt and a 600 watt but his temps are going out the window.hes venting with a RVK/LTI large fan 200mm 8" 750m³ / hour but still the temps going mad after 4 hours lights on the temp starts creeping up over 78 heading upwards of 80s themn he has to turn of the 600 and 1 x 1000 watt until the temps lower. i Know he could add a biger fan but the noise would then becom a problem cuse he is borderline with the noise of the exaust and inlet .He swithched carbon flilters to the new odorsok but that only helped a bit. im thingkin loose some light and get a mover but would be greatfull if you could add some expertise on this:thumbsup: for us. so they can get best use of this space and equipment .Do you think removing the reflectors and hanging the bulbs would be helpfull or detremental to this problems.thatnks in advance davey the postman

I feel like you're missing a giant part of lighting by not mentioning T5's!

I do luv my T5's but I only use them for vegging and mothers. KDspecial does an awesome job with them for flowering too but he's got a seriously green thumb. Normally I don't think they offer the light penetration for flowering anything but short LST'd plants or scrog.

I do gotta say the T5's produce the shortest internodes I have ever seen....I've had a mother under them that was 4 months old and was only 20" tall.

Quote:

---

Originally Posted by doco

I do luv my T5's but I only use them for vegging and mothers. KDspecial does an awesome job with them for flowering too but he's got a seriously green thumb. Normally I don't think they offer the light penetration for flowering anything but short LST'd plants or scrog.

I do gotta say the T5's produce the shortest internodes I have ever seen....I've had a mother under them that was 4 months old and was only 20" tall.

---

I use a 2 bulb HO T5 for my veg and mothers also. I think it's by far the best bang-for-buck and energy consumption value for veg.